[time-nuts] An example of phase noise

[Poul-Henning Kamp]

In message <44E89DD9.7090303 at febo.com>, John Ackermann N8UR writes:

>Thought this might be interesting.  I took a spectrum analyzer shot of
>my ICS525 "Clock-Block" synthesizer at 250MHz, and overlaid it with a
>shot of an RF signal generator (Marconi 2202A) at the same frequency,
>and using the same reference source.
>
>The 2202A is designed for bench use and isn't noted for particularly
>good phase noise, but you can see the dramatic difference between the
>two units (the ICS525 is in red, the 2202A in cyan).
>
>That's why the Clock-Block isn't recommended for RF use!

Have you played with the various PLL configurations that give the
same output frequency to see what difference they make ?

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